I know that you want to give your kids that big breakfast to send them off right, but it will mostly likely just make them sleepy.
If they don't usually eat breakfast, get them to eat a piece of fruit or protein bar. If they do usually eat breakfast, just add one more small thing.
And please send a snack with them for their break during the test. A banana or some almonds and raisins are a good way to go. Something easy but not full of sugar. No sugar high means no sugar low!
Test Prep is a marathon on a sprit. Don't expect over night success.
The SAT and ACT tests your skills and knowledge from your whole school experience. Preparing for them takes time and practice.
Lots and lots of practice.
If you do nothing else, get real practice tests from the test makers and practice them on paper.
Being familiar with the test is the best thing you can do for yourself.
Do not walk into any test without the proper tools.
What to take:
Good Pencils - Ticonderoga pencils are great. Don't use cheap pencils that break all the time. And do NOT use a mechanical pencil. The pointy tip takes longer to fill in the bubbles.
Two Calculators - Yes two. One could fail you.
Erasers - Get the white ones. They don't smear when you erase and they make a handy fidget spinner.
Layers - You never know if your classroom will be cold or hot so dress in layers.
Snack and Water - You'll have a break. You'll be tired. Get some energy from a healthy snack.